#include"mystack.h"
#include<stdio.h>
int main(void) {
	Node* top = NULL;
	push(&top, 1);
	push(&top, 2);
	push(&top, 3);
	push(&top, 4);

	printf("%d\n", pop(&top));
	printf("%d\n", peek(top));
	return 0;
}